Elevator platform leveling system



July 21, 1959 R. w. SMITH ET AL ELEVATOR PLATFORM LEVELING SYSTEM 2 Sheets-Sheet 1 Filed Jan. 28, 1958 2 w 5 0 S w m 6 m m w n .H. m mnw mm F VMU & z mfi m m WA TT M RR EE E BB N w 8 7 RR M v l. 7 nd O 0\ a b 5 R a 4 v V w Y 3 M. W B 3 6 5 3 \3 G u F 5 J M 5& 4& 7 7 3 a J 2 9 2 4 w 2 S\: 4 2 1a m. k V /2 S R J& a a a 2 Q Q L July 21, 1959 R. W. SMITH ET AL ELEVATOR PLATFORM LEVELIalG SYSTEM Filed Jan. 28, 1958 2 Sheets-Sheet 2 INVENTORS ROBERT W. SMITH ROBERT A. VAUGHAN CORBETT MAHONEY, MILLER & RAMBO WMW ATTORNEYS 2,895,568 ELEVATOR PLATEORM LEVEIJINGSYSTEM Robert W. Smithand Robert A. Vaughan, Columbus,

Ohio, assignors, by mesne assignments, to Dresser Industries, Inc., Dallas, Tern, a 'corporation pf'Delaware Application January 28, 1958, Serial No. 711,591 4 Claims. c1. 187-76) This invention relates to an elevatorplatform leveling .system. More specifically, it relates to a-leveliug system for use with the elevator of a vehicle parking garage of the mechanical type.

- Mechanical parking garages usually comprise abuilding structure which is provided with amultiplicity of vertically superposed, laterally adjacent, vehicle-receiving stalls in combination with a horizontally movable elevator-tower structure having an elevatorvertically movable-thereon so that the elevator is operable to move vehicles in both horizontal and vertical. planes to bring each of=them into registry with a. selected. stall. Inthe copending U.S. patent application of Robert WQSmith, Serial No. 626,045, filed December. 3, 1956, now Patent .No.- 2,846,186, there is disclosed a mechanical-parking garage which employs a vehicle-handling ortransferring dolly which moves on orolf the elevator and the respec- -tive floors or decks of the garage. -Boththeelevatdr and the floors are provided with guidetracks for the dolly and it is necessary that the elevator be brought to the exact level of afloor or deck to.or.from..which the dolly is to be transferred. The level must be accurate so that the guide track on the elevator and that on the respective deck or floor will be at the same level, in order to prevent jamming at the jointsbetweenthe respectiveguides. '--In the past, the elevator platform is. movedand. indexed relative to the decksor floors-merely. by visual reference. This is a dilficultand time-consuming operation and there -is.no positive assurancethatthe elevator will be at the exact level of the flooror deck, sinceleveling depends on the skill of the particularoperator.

Itis, therefore, one of the main objects ofithis invention to provide in .associationwith aneleVator ofthe .type indicated, a levelingsystem. for. quickly and positively locating the elevator at a selected declcor'floor .of a mechanical parking garage orathelike.

I It isanother object of this invention tosprovidetan elevator platform leveling systemforleveling the elevator platform with aselected flooror deck. which does not dependv on the skill of thetoperatorin leveling ,the platform with I the selected floor, or ,deck.

-It isa furtl 1er object of this inveution to provide an elevator platform leveling system which will'not interfere withthe normalfast verticaltravel ofthe elevator platform, .and one which will automatically and positively bring the platform .to the correctlevelr as. the :same approaches the parking stalliioor or deck selected by the ,operator.

Still another object of thisinvention isto provide an elevator platform leveling. system of the type indicated which will not interfer'eiwith the required horizontal moyementof the elevator platform along the selected floor or deck and will maintain suchplatform level with thefloor or, deck during such horizontalmovement therealong.

Other objects will be apparent. 7

According to this inventiomthereis provided, a level ing system which preferably includes hydraulic rams States Patent 7O areaas between. he ind v dua p r s stalls a the. Bui d- .m he ading station- 2. .,w 1 .the ar a at, th flo r. srae .v adjacent t a t W1 Willbe 2,895,568 Patented July 21, 1959 2 carried at-the; four-corners, of the elevator platform. These rams are, provided with'levelingmembers'which are adapted to, be projected over the deck or floor with which the platform is to be leveled. These rams areactuatedautomatically through an electrical system controlled by theoperaton The electric control system issuchthat the operator can control the elevator to quickly move it to a level slightly above the'selected floor .or deck and .thenbyihe proper selectionof a control causethe platform todescend slowly to such floor or deck while'simultaneously actuating the rams to extend the leveling members into floor or deck-engagingpositions so that when the platform comes into. vertical registry with the floor or deck it will be automatically stopped and held-level therewith by the projecting leveling members. These leveling members preferably are in the form of rollers which willpermit free horizontal movement of the elevator platform along the selected floor or deck. When it is desired to move the elevator up or down to a diiferent level at relatively high ,speed, the present system functions automatically to retract the leveling-members into such positions that they will not interfere with ordinary vertical movement.

"through thegarage and showing-the levelingtinits on-Ithe elevator; platform.

Figure 3 is an enlargedsectional View; taken, axially through one. of the. hydraulic leveling ram units.

Figure, 4 ,is a transverse secticpnal view-taken along line 44 of Figure. 3. e

:Figure 5; is a schematic view. of the electric ..control circuit of the leveling. system.

Eigurey6 is, a schematicyiew of the hydrauliccontrol circuit of the leveling. system.

:lieferringnow to the. drawings, 7 and morev particularly to. Figures l and. 2 thereof,; a parking garagehbuilding structure is illustrated generally. by,.reference numeral 20. .In the,.form. of..-b1iilding structure illustrated.in.Fig-

.ures and 2, the same comprises. vertically arranged .outer walls 21 extending upwardlyfrom a floor or. ground leyelZZL The buildingstructure further provides, a. multiplicity ofindividual parking .stalls 23 preferably, ,arranged -in;.eleva t ed relation to the-,firstfioor 01":gI Ql 1l1d level. of the building structure. 1 The. individual stalls. 23-,

at each floorlevel, are arranged in horizontal .rows ,;.or banks disposed. on each side of andadjacent to acentrally arranged elevator shaft orpassageway. 24, which. extends longitudinally of the. building structure from one; vend thereof to'theother... Adyantageously, the buil ding;struc,- turejs provided at the. ground level 22 thereofwithone ,or moreentrance ,ways.25,,i nto which automobiles or vehicles to. be parked ,may. be. driven from the adjacent street or highway,, {and one or more. exit. waysv 26- from h, ch.u pa ke kc t: disqha edve icles m y. e driven im bu d n str ctu F .Purpo .of ,.0.11-

Venience tI-le ig roundfloor area oif the building sjtruct adj centrthe en ran e w y 25. Wi1lb r in ft as the unloading station 28.

Ea h. ere jot theb. ld nast uc u elfl i gm ids sui able it -s rfac s; 9.,whi h.m fi in ing and appropriately supported by suitable structural given vertical bank of parking stalls 23.

beams and columns. Mounted centrally and longitudinally upon the floor-29 of each parking stall 23 and 1 the floors of the loading and. unloading stations 27 and 28 is a single upstanding guide rail 30 which servesas a means to positively guide and maintain the vehicle-handling and transferring dolly, shown at 31, ina straight'line during its movement to and from the associated elevator apparatus.

Positioned within the elevator shaftway' 24 and-arranged for movement longitudinally thereof in a horizontal plane is an elevator-supporting-tower structure 32 which extends the full height of the building structure.

The elevator-supporting tower structure 32 comprises a base frame section 33 which may advantageously carry a plurality of spaced flanged wheels 34 mounted for rolling movement upon relatively stationary rails 35. As illus- "trated in Figure 1 of the drawings, the rails 35 are mounted upon a suitable foundation 36 provided below the first floor level of thebuilding structure, but-1f desired, it'will be understood that the elevator tower structure 32 may be mounted at or in elevated relation to the first floor level, as for example, at the second floor level, when it is desired to provide free passage area between opposite sides of the building structure at the first floor level and on either side of the loading and unloading stations 27 and 28.

Mounted for guided vertical movement within the elevator-supporting tower structure 32 is an elevator platform 37. The platform 37 is provided on either side with 'suitable diagonally and upwardly extending supporting braces 38 which are connected with a hoisting cable 39 adapted to be retracted and extended relative to the elevator tower structure, by a suitable hoisting apparatus indicated diagrammatically at 40 in Fig. 1.

Advantageously, one or more of the flanged wheels 34, carried at the base section of theelevatonsupporting tower 32, may be driven in rotation by" appropriate drive means, not shown, in order that the elevator-supporting tower structure may be driven bodily longitudinally and horizontally of the shaft or passageway 24, to thereby align the tower structure and elevator platform a Thus, it will readily be understood by those skilled in the art, that the elevator platform 37 isarranged for simultaneous movement in both horizontal and'vertical planes relative to the building structure throughsimultaneous operation of the drive mechanisms'associated with the traction wheels 34 and the hoisting mechanisms 40,

such mechanisms preferably being under the control of a 'single operator stationed upon the elevator apparatus.

As illustrated diagrammatically in Fig. 1, the elevator platform-hoisting apparatus 40 includes a single-acting 'hydraulic ram or motor 40a which is provided with an extensible plunger 40b whose outer end is connected with a pivotal lever 40c which, in turn, is connected with a traveling block 40d of a suitable movement-multiplying block and tackle system embodying the hoisting cable 39 and one or more crown blocks 40e. The crown block or blocks 40c are advantageously stationarily mounted in the top of the tower structure 32, while the ram 40a 'and its associated lever and movement-multiplying apparatus may be mounted along one side of the vertical columns or posts of the tower structure to be movable horizontally in association therewith. As will be understood, vertical movement of the elevator platform 37 in an upward direction is accomplished by the extension matically Fig. l. l The operating circuit for the ram 40a controls the flow of hydraulic fluid to and from the cylinder of the ram, and toward this end, comprises a two position, three-way valve 41'which is operable to connect the inlet-outlet port 42 of the ram 40a either with an exhaust line 43, containing a restriotor 44, or with a conduit 45 communicating with a solenoid-actuated, three-way reversing valve 46. The reversing valve 46 includes a first port 47 which is connected to receive pressure fluid from a hydraulic pump P1 having an inlet connected with a fluid supply reservoir 48. The outlet conduit of the pump P1 is provided, in the usual manner, with a pressure relief valve by-pass 47a through which pressure fluid from the pump may be by-passed to the reservoir when the valve 46 occupies a neutral or closed position. The valve 46 further comprises an outlet port 49 connected directly with the reservoir 48. Advantageously, the valve 46 may comprise the usual standard type of balanced spool, three-way reversing valve which includes the solenoids S4 and S5 energizable selectively toshift the valve 46 between positions to connect the line 45 either with the reservoir 48 or with the pump P1. Normally, the threeway valve 41 is spring pressed to a position to connect the inlet-outlet port 42 of the ram 40a with the line 45, but may be shifted upon energization of the solenoid S3 to connect the inlet-outlet port 42 with the restrictor exhaust line 43, .as will be hereinafter more fully explained.

As previously stated, the present invention is concerned primarily with an improved system or apparatus for leveling the elevator platform 37 with respect to the individual floors of the parking stalls, and toward this end, there is stationarily mounted upon each of the four corners of the elevator platform 37, a fluid-actuated leveling unit 50. The leveling units 50 are preferably in the form of hydraulic rams or motors of the type shown in Figures 3 and 4. Each ram unit comprises a cylindrical housing 51 which is stationarily attached to the elevator platform 37. Mounted for reciprocation in the housing 51 is ashaft 52 which reciprocates within a bearing 53 disposed within the housing. Keys 54 are provided between the housing 51 and the shaft 52 to permit reciprocation of the shaft within the housing without rotation therein. The shaft 52 is reciprocated by means of a piston rod 54 which is threaded into the inner end thereof, as indicated at 55. A piston 56 is connected to the rod .and disposed within a double-acting hydraulic cylinder 57 which has the lines 58 and 59 connected to opposite ends thereof. On the other end of the shaft 52 there is rotatably mounted an antifiiction roller 60. Between the roller 60 and the. outer end of the housing 51 is an expansible dust sleeve 61 connected respectively to the housing and shaft to prevent entrance of dust and dirt into the housing. In the retracted position of the ram 50, as shown in full lines in Figure 3, the leveling roller 60 will be within the boundary of the elevator platform 37. However, the cylinder-piston unit can be actuated to move the roller 60 outwardly so that it may extend over an adjacent floor or deck 29, as indicated by the dotted line position of Figure 3. When the ram is in such extended position, the roller 60 engages a leveling strip 62 provided along the edge of each floor 29 adjacent the shaft 24 and extending the full length thereof. Thus, it will be apparent that if the platform 37 is moved above a selected floor 29 and then the rams 50 are actuated to position the leveling rollers 60 over the associated edges of the floor 29, the elevator platform 37 can then be lowered until the rollers 60 engage the leveling strips 62 on the opposite sides of the shaft 24, at which time the elevator platform 37 is maintained in exact horizontal alignment with the selected floor 29.

.The platform leveling units 50 are operated by means of a hydraulic circuit illustrated in Figure 6. The ramadvancing areas of each of the cylinders 57 are connected in parallel through the conduits 58 with a manifold conduit 5 8a which, in turn, is connected with one of the motorports .of a solenoid actuated reversing valve 65.

The reversing valve 65 has an oppositemotor port connected with a manifold conduit '59ajin fluid communication with each of the iconduits 59 leading to the ramretracting. areas of the cylinders 57 of each of the levelingunits 50. The pressure inlet port of the reversing valve 65 is connected by means of the conduit 66 with the outlet of. a hydraulic pump P2 whose inlet communicateswith a reservoir 68, and which is provided withthe usual by-pass line 69 and pressurerelief valve 69a operable to recirculate pressure fluid between the outlet of the pump P2and the reservoir 68 in response to a predetermined build-up in pressure at the outlet sideofthe pump. The valve.65 is of the ordinary balanced spool type and is adapted to be operated uponselected energization ofthe' solenoids S1 and S2 so as to direct press'urefluid from thepump P2 into either of the lines 58a or.59a while connecting the opposite line with exhaust. Upon energization of the solenoid S1, pressure fluid from the pump P2 is introduced into the'manifolcl 59a and thence to the ram-retracting areas of each of the cylinders 57 of the leveling units 50. At the same time, the ram-advancing areas ofthe cylinders 57 are connected with exhaust by Way of the lines 58 and 58a and the exhaust port of the valve 65 Conversely, upon .energization of the solenoidSZ, the Valve 65 is shifted to conduct pressure fluid through the manifold 58a and into each of the ram-advancing areas of the cylinders 57 while connecting the ram-retracting areas thereof with exhaust.

Figure 5 of the drawings illustrates, diagrammatically, an electrical control circuit employed in the' semiautomatic control of-the vertical movement of the elevator platform 37 and the extension and retraction ofthe platform leveling units 50. Operating current is supplied to the circuit through the power lines L1 and L2, and the circuit includes three normally open, manually controlled push button switches 73, 74 and 75, respectively. The switches 73, 74 and 75 are mounted in convenient location upon the elevator platform and are readily accessible to the operator. The switch 75 is designated as the up switch, and when closed, initiates upward movement of the elevator platform 37 by energizing the solenoid S5 which is associated with the reversing valve 46. Upon energization of solenoid S5, pressure fluid from the pump P1 is directed through the line 45 and three-way valve 41 into the ram-advancing area of the elevator ram 40a to cause upward movement of the elevator platform. Simultaneously upon energization of the solenoid S5, a relay switch R5 is closed to energize the solenoid S1 of the valve 65 so as to assure retraction of the leveling units 50. The elevator platform 37 will continue to move upwardly so long as the switch 75 remains closed. As the elevator platform 37 reaches a height slightly above the level of a preselected floor 29, the push button switch 75 is released and the upward movement of the elevator platform 37 is arrested upon deenergization of solenoid S5. The operator then closes the push button switch 73 which results in the simultaneous energization of solenoid S2, associated with the reversing valve 65, and the solenoid S3 connected to shift the three-way valve 41. Energization of solenoid S2 shifts the valve 65 so as to direct fluid pressure from the pump P2 into the ram-advancing areas of the leveling units 50 in order to extend the shafts 52 and their associated rollers 60 outwardly from the four corners of the platform in position to engage the upper surface of the preselected floor 29. At the same time, energization of solenoid S3 shifts the valve 41 so as to connect the fluid inlet-outlet port 42 of the elevator ram 40a with the exhaust line 43 containing the restrictor 44, to thus permit the elevator 37 to descend at a relatively slow rate of speed by gravity. As the elevator platform 37 slowly descends, the extended rollers 60' of the leveling units 50 eventually engage the upper surface of the preselected floor 29 to arrest further downward movement of the elevator platform 37 automatically, and

to bring the platform 37 into exact horizontal registryor alignment with the preselected floor. I

.At this time, a vehicle may be unloaded from the platform 37 and transferred intoa preselected stall 23, or a parked vehicle may be transferred from a preselected stall 23 onto the elevator platform 37. .After the vehicle transfer operation has been completed, and it is desired to lower the elevator platform 37 to the ground floor level, or to alevel below that of thepreselected floor, the operator momentarily presses the up switch 75 to takethe Weight of the elevator off of the leveling units. 50 and thenv presses the switch 74 designated down. Closure of switch 74 energizes solenoid S4 associated with thereversing valve 46 to shift the latter to a position to connect the line 45 with theexhanst port 49 and permit substantially unrestricted flow of fluid from the elevator ram 40a through the valve 41, line 45, and valve 46 to the reservoir 48. Thus the platform 37 will descend at a relatively rapid rate by gravity, and descending movement, is arrested automatically upon release of the down switch 74, thus deenergizing solenoid S4 and permitting the valve 46 to return ,to its neutral position trapping fluid in the line 45. In this regard, it will be noted thatthe three-way valve 41 is normally spring. pressed to a position connecting the inletoutlet port 42 of the ram 49a with the line 45, and this latter position of the valve 41 is maintained at all times when the solenoid S3is deenergized. Connected in parallel circuit with the solenoid S4 is a relay switch R4 which is energizedsimultaneously with solenoid S4 upon closure of switch 74. The armature of relay R4 is connected in series circuit withthesolenoid Slbetween the power lines L1 and L2, andupon energization of vrelay R4, solenoid S1 is energized to assure retraction of the platform-leveling units 50.

Thus, it'will be seen that through the combined electrical and hydraulic control circuits illustrated, the elevator operator is enabled to elevate or lower the platform 37 at comparatively high rates of speed through proper manipulation of the push button switches 74 and 75. At the same time, when the operator desires to bring the elevator platform into alignment with a preselected floor or stall, he may, simply by raising the elevator slightly above such preselected floor, cause automatic leveling of the platform with the preselected floor by pressing the inc down switch 73. As previously stated, closure of switch 73 results in simultaneous extension of the leveling units 50 and the lowering of the platform 37 at a controlled low rate of speed. Due to the function of the leveling units 50 in arresting downward movement of the elevator platform 37 by engagement with the upper level of a preselected floor, the operator is relieved of the normally arduous task of hunting the elevator platform 37 through a series of up and down movements to bring the elevator platform into the necessary exact horizontal alignment with the preselected floor. At the same time, long distance vertical hauls may be accomplished at relatively high speeds through the proper operation of the normal up and down switches 75 and 74, respectively.

It will be apparent from the above description that this invention provides a leveling system for the elevator platform of a mechanical garage or the like. The leveling action, when selected, is automatic and positive. During fast up and down operation of the elevator, the leveling system does not interfere with the operation of the elevator. Furthermore, when the leveling action is completed and the elevator platform is located level with the desired floor, the leveling units do not interfere with any necessary horizontal travel of the elevator platform. Further, the location of the leveling units at the four corners of the elevator platform enables such units to support the platform with stability, and prevents the platform from tipping of tilting when vehicles are being transferred to and from the elevator platform.

. According to the provisions of the patent statutes, the principles of this invention have been explained and have been illustrated and described in what is now considered to represent the best embodiment. However, it is to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

Having thus described this invention, what is claimed is:

1. In a mechanical parking garage or the like having a plurality of vertically superposed decks disposed alongside of a horizontally elongated vertically extending elevator shaft, an elevator tower mounted for movement horizontally along said shaft and extending vertically thereof, an elevator mounted for vertical movement on said tower to different levels adjacent said decks, a plurality of leveling units carried on the elevator and movable from a retracted position within the confines of the elevator to an extended position vertically overlying a selected deck with which the elevator is to be leveled, said leveling units carrying leveling members engageable with the selected deck for movement therealong to permit horizontal movement of the elevator therealong upon horizontal movement of said tower along said elevator shaft, and control means for moving said units between said retracted and extended positions.

2. The combination of claim 1 including hoist means connected to the elevator for moving it vertically on the tower to the different levels adjacent said decks, said control means including a first up control operatively connected to the hoist means for controlling it to move the elevator upwardly at a relatively fast speed, a second down control operatively connected to the hoist means for controlling it to move the elevator downwardly at a relatively fast speed, means actuated by said first and second controls and operatively connected to said levellog units for retracting said leveling units upon actuation of said first and second controls to move the elevator upwardly or downwardly, and a third down control operatively connected to saidhoist means and to said leveling units for extending said leveling and to simultanek ously operate said hoist means to cause the elevator to move downwardly at a relativelylow rate of speed't'o engage said leveling members with the selected deck.

3. The combination of claim 2,in which said. hois means is hydraulically operated and includes an electro magnetic reversing valve for controlling up and down movements at relatively fast speed and a second electro magnetic valve for controlling down movement at a rela-' tively slow speed, an electric circuit in which said elec tromagnetic valves are connected, said first and second controls being up and down electric switches connected in said circuit for moving said first valve into its reversing positions, said leveling units being hydraulic rams, a third electromagnetic reversing valve for controlling said leveling rams, said third control being a leveling electric switch connected in said circuit with said second and third valves for controlling downward movement of the elevator at a relatively low speed and for simultaneously moving said rams into extended position.

4. The combination of claim 3 in which the leveling members carried by said rams are rollers which engage horizontal leveling strips carried by said decks for rolling therealong upon horizontal movement of the leveled elevator.

References Cited in the file of this patent UNITED STATES PATENTS Edwards et al. Dec. 11, 1956 

